1,2-diacylglycerol content in myocardium from spontaneously hypertensive rats during the development of hypertension.
1,2-Diacylglycerol (DAG) has been considered to play an important role as an activator of protein kinase C in the signal transduction of inositol phospholipid metabolism. To examine the relation of 1,2-DAG in heart tissues to cardiac hypertrophy associated with hypertension, we measured the amount of 1,2-DAG in spontaneously hypertensive rat (SHR) hearts at 4, 10 and 20 weeks of age, and in age-matched normotensive Wistar-Kyoto (WKY) rat hearts using thin-layer chromatography with flame ionization detection (TLC-FID). Significant cardiac hypertrophy was found in 4-week-old SHR, while SHR did not yet have significant hypertension. Major phospholipids such as phosphatidylcholine and phosphatidylethanolamine increased from 4 to 20 weeks in the myocardium, but there was no difference between the two strains. The cholesterol levels of 4- and 20-week-old SHR were significantly higher than WKY rats. The 1,2-DAG contents of SHR hearts were significantly higher than WKY rats at 4 weeks. An increase in the RNA content was also observed in 4-week-old SHR hearts. However, analysis of the fatty acid composition of 1,2-DAG revealed no difference between the two strains. However, there was no significant difference in the 1,2-DAG content or in its fatty acid composition between SHR and WKY rat hearts at 10 and 20 weeks of age. It is suggested that an increase in the 1,2-DAG content of SHR hearts during the early stages appears related to the initiation of cardiac hypertrophy in SHR hearts before developed hypertension.
Kondo
J
J
Second Department of Internal Medicine, Nagoya University School of Medicine, Japan.
Yamada
Y
Y
Okumura
K
K
Hashimoto
H
H
Ito
T
T
Satake
T
T
D000375:Aging / Q000378:metabolism; D000818:Animals; D001794:Blood Pressure; D004075:Diglycerides / Q000378:metabolism*; D006973:Hypertension / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012016:Reference Values; D013599:Systole
C011439:1,2-diacylglycerol; D004075:Diglycerides; D010743:Phospholipids